Although in 2006 private equity activity was booming and larger companies than ever before were bought out, insiders feared the day that it would abruptly end. On two different occasions David Rubenstein expressed this fear. In January 2006, he stated: “This has been a golden age for our industry, but nothing continues to be golden forever".[6] One month later, he emphasized this concern more explicitly: "Right now we're operating as if the music's not going to stop playing and the music is going to stop. I am more concerned about this than any other issue",[7] These concerns proved to be right as at the end of 2007 the buyout market collapsed. This collapse can largely be attributed to the credit crunch, which significantly increased the cost of borrowing. As leveraged loan activity came to an abrupt stop, private equity firms were unable to secure financing for their transactions. As the consequences of the credit crunch unveiled themselves, many previously announced buyouts were cancelled.

In May 2008 David Rubenstein stated: “But once this period is over, once the debt on the books of the banks is sold and new lending starts, I think you'll see the private equity industry coming back in what I call the Platinum Age - better than it's ever been before. I do think that the private equity industry has a great future and that the greatest period for private equity is probably ahead of us.”[8]

David Rubenstein's father was a post office worker earning $7000 annually and his mother a house wife. In a speaking engagement at the University of Maryland, he revealed that his mother wanted him to grow up and become a dentist. Rubenstein has stated that he was once offered to meet Mark Zuckerberg before he dropped out of Harvard but decided against it. This is his single greatest investment regret.[9]

On December 18, 2007, David Rubenstein purchased the last privately owned copy of the Magna Carta at Sotheby's auction house in New York for $21.3 million.[12] He has lent it to the National Archives in Washington D.C.[13] In 2011, Rubenstein gave $13.5 million to the National Archives for a new gallery and visitor's center.[14]

In December 2011, Rubenstein donated $4.5 million to the National Zoo for its giant panda reproduction program.[17] The panda complex was then named the David M. Rubenstein Family Giant Panda Habitat for the next five years and conservation biologists in the U.S. and China who are awarded National Zoo fellowships for their work to save pandas would be named “David M. Rubenstein Fellows."[18]

In November 2013, he bought a copy of the Bay Psalm Book for $14.1 million, the highest price ever paid for a printed book, and pledged to lend it to public collections and exhibitions around the world.[23]

Rubenstein has made several gifts to Duke University. He donated $5 million to Duke's Sanford School of Public Policy in 2002, after which Rubenstein Hall was named for him. In 2009, he donated an additional $5.75 million to the school.[24] In 2011, he also donated $13.6 million to the Duke University Libraries in support of renovating the university's special collections library, which was named the David M. Rubenstein Rare Book & Manuscript Library.[25] In 2012, he donated $15 million to support the university's Innovation and Entrepreneurship Initiative.[26] That same year, he gave another $10 million to support Duke Athletics.[27] In 2013, Rubenstein donated $10 million to fund graduate fellowships and undergraduate internships at the Sanford School of Public Policy.[28]

"When history is written and people talk about the great protests, I don't think that this will be in that category." [42](comparing what in his view were the great civil disobedience efforts of Gandhi and Martin Luther King to the protests by the Working Families Party concerning the tax treatment of private equity firms)

“I analogize [private equity] to sex ... You realize there were certain things you shouldn’t do, but the urge is there and you can’t resist.” [43](speaking at Harvard Business School about the buyout bubble)

"I think it's important to tell people the good and the bad of American history, not only the things that we might like to hear." [22](referring to his wanting to put a face on slavery using his donation to rebuild slave quarters at Monticello)